“It’s not yes, AND! It’s YES! and…”

If you’re in your head, you’re trying to think of what to say or do. You will never, ever need to do that if you are simply reacting to what’s already there. You have everything you need; your scene partner has just given it to you. You just have to let yourself be affected and pushed in a direction by it. If you are in your head, you are looking for answers in the wrong place.